From 0e01a74fb51c52f7a5f29dbb20ef9e783fa81cbc Mon Sep 17 00:00:00 2001
From: Fredrik Mellbin <fredrik.mellbin@gmail.com>
Date: Sun, 30 Mar 2008 15:39:02 +0000
Subject: [PATCH] fix for h264 with b-frame pyramid stuff

Originally committed to SVN as r2161.
---
 FFmpegSource/ffmatroskasource.cpp | 13 ++++++++++---
 FFmpegSource/ffmpegsource.cpp     | 16 ++++++++++++----
 FFmpegSource/ffmpegsource.html    |  2 ++
 3 files changed, 24 insertions(+), 7 deletions(-)

diff --git a/FFmpegSource/ffmatroskasource.cpp b/FFmpegSource/ffmatroskasource.cpp
index 2b3a497fa..223a2ee18 100644
--- a/FFmpegSource/ffmatroskasource.cpp
+++ b/FFmpegSource/ffmatroskasource.cpp
@@ -357,19 +357,26 @@ int FFMatroskaSource::DecodeNextFrame(AVFrame *AFrame, int64_t *AFirstStartTime,
 	unsigned int Track, FrameFlags, FrameSize;
 	
 	while (mkv_ReadFrame(MF, 0, &Track, &StartTime, &EndTime, &FilePos, &FrameSize, &FrameFlags) == 0) {
-		FrameSize = ReadFrame(FilePos, FrameSize, VideoCS, Env);
 		if (*AFirstStartTime < 0)
 			*AFirstStartTime = StartTime;
+		FrameSize = ReadFrame(FilePos, FrameSize, VideoCS, Env);
 		Ret = avcodec_decode_video(VideoCodecContext, AFrame, &FrameFinished, Buffer, FrameSize);
 
+		if (Ret < 0)
+			goto Error;
+
 		if (FrameFinished)
 			goto Done;
 	}
 
-	// Flush the last frame
-	if (CurrentFrame == VI.num_frames - 1 && VideoCodecContext->has_b_frames)
+	// Flush the last frames
+	if (VideoCodecContext->has_b_frames)
 		Ret = avcodec_decode_video(VideoCodecContext, AFrame, &FrameFinished, NULL, 0);
 
+	if (!FrameFinished || Ret < 0)
+		goto Error;
+
+Error:
 Done:
 	return Ret;
 }
diff --git a/FFmpegSource/ffmpegsource.cpp b/FFmpegSource/ffmpegsource.cpp
index fee4359ce..a3ef7915c 100644
--- a/FFmpegSource/ffmpegsource.cpp
+++ b/FFmpegSource/ffmpegsource.cpp
@@ -237,10 +237,13 @@ int FFmpegSource::DecodeNextFrame(AVFrame *AFrame, int64_t *AStartTime) {
 
 	while (av_read_frame(FormatContext, &Packet) >= 0) {
         if (Packet.stream_index == VideoTrack) {
-			Ret = avcodec_decode_video(VideoCodecContext, AFrame, &FrameFinished, Packet.data, Packet.size);
-
 			if (*AStartTime < 0)
 				*AStartTime = Packet.dts;
+
+			Ret = avcodec_decode_video(VideoCodecContext, AFrame, &FrameFinished, Packet.data, Packet.size);
+
+			if (Ret < 0)
+				goto Error;
         }
 
         av_free_packet(&Packet);
@@ -249,10 +252,15 @@ int FFmpegSource::DecodeNextFrame(AVFrame *AFrame, int64_t *AStartTime) {
 			goto Done;
 	}
 
-	// Flush the last frame
-	if (CurrentFrame == VI.num_frames - 1  && VideoCodecContext->has_b_frames)
+	// Flush the last frames
+	if (VideoCodecContext->has_b_frames)
 		Ret = avcodec_decode_video(VideoCodecContext, AFrame, &FrameFinished, NULL, 0);
 
+	if (!FrameFinished || Ret < 0)
+		goto Error;
+
+// Ignore errors for now
+Error:
 Done:
 	return Ret;
 }
diff --git a/FFmpegSource/ffmpegsource.html b/FFmpegSource/ffmpegsource.html
index e32379c32..78134c523 100644
--- a/FFmpegSource/ffmpegsource.html
+++ b/FFmpegSource/ffmpegsource.html
@@ -166,6 +166,8 @@ Note that --enable-w32threads is required for multithreaded decoding to work.
 <h2>Changes</h2>
 <ul>
 <li>1.17<ul>
+<li>Changed error handling slightly in video decoding (most errors are still ignored)</li>
+<li>Fixed a bug where the last frame(s) wouldn't be returned properly in h264 with b-frames+pyramid</li>
 <li>Updated FFmpeg to rev X</li>
 </ul></li>